Littérature scientifique sur le sujet « Incidental nonfunctioning endocrine pancreatic tumor »

Most pancreatic neuroendocrine tumors (NETs) are detected incidentally and arise in the endocrine tissues. NETs can secrete hormones and result in clinical syndromes. However, between 50 and 75 percent of pancreatic NETs are nonfunctioning. Ultrasonography shows a well-circumscribed mass with a smooth margin and round or oval hypoechoic shape. A 38-year-old woman visited our hospital with mild upper abdominal discomfort. We visualized an oval hypoechoic mass with inner hyperechogenicity after water intake in the stomach and position change. The patient underwent surgery, and the mass was diagnosed as pancreatic NET.

AIM: Preoperative suspicion of malignancy in nonfunctioning pancreatic neuroendocrine tumors (pNETs) is mostly based on tumor size. We retrospectively analyzed the contrast enhanced ultrasound (CEUS) features of a series of histopathologically proved nonfunctioning pNETs. METHODS: In this retrospective study, 37 surgery and histologically proved nonfunctioning pNETs were included. All pNETs lesions were incidentally detected by transabdominal ultrasound. B mode ultrasound (BMUS) and CEUS features were reviewed and analyzed. 52 histopathologically proved pancreatic ductal adenocarcinoma (PDACs) lesions were included as a control group. RESULTS: All nonfunctioning pNETs patients showed no typical clinical symptoms. No significant differences were observed in size, echogenicity or internal color flow imaging signal between pNETs and PDAC patients (P > 0.05). Most of nonfunctioning pNETs showed a well-defined tumor margin. The presence of pancreatic duct dilatation was less frequently observed in nonfunctioning pNETs patients (P < 0.05). After injection of ultrasound contrast agents, homogeneous enhancement was more commonly observed in nonfunctioning pNETs group (P < 0.05). During arterial phase of CEUS, most of nonfunctioning pNETs were hyper- or isoenhanced (32/37, 86.5%), whereas most of PDACs were hypoenhanced (34/52, 65.4%) (P < 0.05). Nonenhanced necrosis area was more commonly detected in PDACs (P = 0.012). CONCLUSIONS: CEUS features are helpful for preoperative non-invasive differential diagnosis of nonfunctioning pNETs, assisting further clinical decision-making process.

Morphologic irregularities of the pancreatic duct are often noted on abdominal imaging studies obtained for unrelated symptoms or conditions. We report the case of a patient who was found to have an incidental, isolated pancreatic duct dilatation on multiple imaging studies and who was found to have a nonfunctioning pancreatic endocrine neoplasm at resection. His prognosis is excellent based on the histology of the lesion and a curative resection. This case highlights the importance of fully investigating incidental pancreatic duct abnormalities regardless of the setting in which they are found.

Hemorrhage from gastric varices due to left-sided portal hypertension is an unusual presentation for pancreatic endocrine tumor. A case of pancreatic endocrine tumor presenting with gastric variceal hemorrhage secondary to left-sided portal hypertension associated with splenic vein occlusion is presented. A 53-year-old man with hemorrhage from isolated gastric varices was referred to our hospital. Laboratory studies revealed normal liver function. Surveys to identify the cause of gastric varices by an abdominal CT, MRCP, and abdominal angiography revealed splenic vein occlusion secondarily attributed to the pancreatic tail tumor and splenomegaly. The pancreatic tumor was suspected to be a resectable endocrine tumor. A distal pancreatectomy, splenectomy, partial resection of the gastric fundus, and limited lymph node dissection were performed. By the histological examination, the diagnosis of nonfunctioning pancreatic endocrine tumor with malignant potential was determined. Three years after the surgery, the patient is doing well and reveals no sign of recurrence. In this case, the unusual presentation for pancreatic endocrine tumors such as a gastric variceal hemorrhage had an advantage that led to early presentation prior to the development of metastases with possible curative surgery.

Introduzione: l’attuale diffusione e maggior accessibilità delle tecniche imaging negli ultimi anni hanno aumentato l’incidenza di riscontro di neoplasie endocrine non-funzionanti del pancreas (NF-PNETs) asintomatiche. I NF-PNETs incidentali (I-NF-PNETs) solitamente presentano diametro e stadio minori rispetto ai NF-PNETs sintomatici (S-NF-PNETs) ed il riscontro occasionale sembra rappresentare un fattore prognostico favorevole sia per lo stadio di malattia sia per il grading istologico. Vi è comunque una assenza di dati circa la gestione dei I-NF-PETs potenzialmente non aggressivi. Obiettivi:1) definire il comportamento biologico dei I-NF-PETs sottoposti a resezione chirurgica e 2) valutare una eventuale politica di Follow-Up nella gestione dei I-NF-PETS di stadio I. Metodi: sono stati inclusi nello studio tutti i pazienti con diagnosi confermata all’istologia di NF-PET sporadico sottoposti tra il 1990 ed il 2011 a resezione chirurgica presso il Dipartimento Chirurgico dell’Università di Verona ed il reparto di chirurgia dell’Opedale S. Cuore-Don Calabria di Negrar. E’ stata eseguita una valutazione comparativa delle caratteristiche demografiche, cliniche e patologiche tra I-NF-PETs e S-NF-PETs. E’ stata eseguita l’analisi statistica adeguata per identificare le differenze statisticamente significative del comportamento biologico dei I-NF-PETs versus gli S-NF-PETs. Risultati: Sono stati evidenziati 131 pazienti (42.8%) con diagnosi di I-NF-PET e 175 pazienti (57.2%) con diagnosi di S-NF-PET. Non è stata riscontrata differenza di sesso tra i due gruppi (p=0.752). L’età media è stata per i maschi: 62 anni (range 24-83) nei I-NF-PETs e 55 anni (range 17 – 78) per gli S-NF-PETs; per le femmine rispettivamente di 55 anni (range 35 – 72) e 53 anni (range 25 – 74), p= 0.223. Gli I-NF-PETs si sono riscontrati più frequentemente a livello del corpo-coda del pancreas (65 casi, 49.6%), mentre gli S-NF-PETs si sono localizzati maggiormente a livello del corpo-coda (56.6%) e della coda (38.3%) (p= <0.001). Si sono ottenuti margini di resezione microscopicamente liberi da malattia (R0) in 123 pazienti (93.9%) con I-NF-PET ed in 131 pazienti (74.9%) con S-NF-PET (p<0.001). Il diametro medio riscontrato è stato di 20 mm (range 7 – 120) per gli I-NF-PETs e di 35 mm (range 5 – 140) per gli S-NF-PETs; p= 0.016. Comunque gli I-NF-PETs di stadio I si sono riscontrati più frequentemente rispetto agli S-NF-PETs (p<0.001). Ugualmente, si è riscontrata una localizzazione linfonodale di malattia (N1) nel 44.6% dei pazienti (78 casi) con S-NF-PET rispetto al 20.6% (27 casi) dei pazienti con tumore incidentale; p<0.001. Un paziente con I-NF-PET allo stadio I ha dimostrato avere una malattia aggressiva. Questo caso inizialmente era stato classificato come benigno ed era stato sottoposto ad intervento di enucleazione (R0), ma è stata evidenziata la comparsa di metastasi epatiche a distanza di 28 mesi dall’intervento chirurgico. In questo caso, tuttavia si era evidenziata, alla imaging radiologica preoperatoria, una dilatazione del dotto di Wirsung condizionata dalla neoplasia ed alla immunoistochimica si era evidenziata una positività alla serotonina. Queste caratteristiche possono rappresentare nella maggior parte dei casi una tendenziale aggressività della neoplasia. Da settembre 2007 a settembre 2011 sono stati inoltre considerati 19 pazienti con diagnosi di I-NF-PET. In tutti i casi si trattava di NET-G1 con un diametro medio di 15 mm (range 9-20). In nessun caso si erano evidenziate caratteristiche radiologiche di potenziale aggressività neoplastica (tra cui la presenza di dilatazione del dotto di Wirsung). Il Follow-Up è stato condotto per tutti i pazienti con una mediana di 22 mesi (tange 6-48). Tutti i pazienti sono risultati vivi, asintomatici con neoplasia stabile senza evidenza di progressione di malattia. Conclusioni: questo studio dimostra che i pazienti con NF-PET di riscontro incidentale rappresentano circa il 40% dei NF-PETs resecabili e che la diagnosi di I-NF-PET è aumentata negli ultimi anni. La diagnosi incidentale sembra rappresentare un fattore prognostico importante sia per le caratteristiche istopatologiche di malattia sia in termini di sopravvivenza e ricorrenza di malattia dopo resezione. Tuttavia la chirurgia pancreatica evidenzia un alto indice di comorbidità post-operatorie e per le neoplasie incidentali del diametro < 20 mm senza caratteristiche radiologiche di sospetta aggressività, si potrebbe proporre il Follow-Up clinico-radiologico.
Introduction: the widespread use of imaging techniques allowed increasing incidentally detection of asymptomatic non-functioning PNETs (NF-PNETs). Incidental non-functioning PNETs (I-NF-PETs) are usually smaller and lower in stage than symptomatic NF-PNETs (S-NF-PETs) and incidental detection seems to be an important favourable prognostic factor even after accounting for tumor stage, grade and location. There is a complete lack of data as regards of the admitted correct management of asymptomatic patients with potentially benign NF-PET. Aims:1) to define the biological behaviour of I-NF-PETs who underwent surgical resection and 2) to evaluate a follow-up policy in the management of I-NF-PNETs at stage I. Methods: All patients with a pathologically confirmed diagnosis of sporadic NF-PETs who underwent resection at the Departments of Surgery of the University of Verona and of Ospedale “Sacro Cuore – Don Calabria” of Negrar between 1990 and 2011 were included. A comparison of demographic, clinical and pathological characteristics between I-NF-PETs and S-NF-PETs was made. Statistical analyses were performed to identify differences in biological behavior between I-NF-PETs and S-NF-PETs. Results: A total of 131 patients (42.8%) had diagnosis of I-NF-PETs and the remaining 175 patients (57.2%) had diagnosis of S-NF-PETs. No sex predilection was observed (p=0.752). The median patient age was for male: 62 years (range 24 – 83) and 55 (range 17 – 78) with I-NF-PET and S-NF-PET diagnosis respectively; for female was 55 years (range 35 – 72) and 53 (range 25 – 74) with I-NF-PET and S-NF-PET (p= 0.223) respectively. The most common location of I-NF-PETs was in the body-tail of the pancreas (65 cases, 49.6%), whereas S-NF-PETs were most commonly founding both in the body-tail (56.6%) and in the head of the pancreas (38.3%) (p= <0.001). Clear surgical margins (R0) were obtained in 123 patients (93.9%) with I-NF-PET and in 131 patients (74.9%) with S-NF-PET (p<0.001). Median tumor size was lesser for I-NF-PETs with a median of 20 mm (range 7 – 120), than S-NF-PETs (median 35 mm; range 5 – 140); p= 0.016). Therefore T1 incidental tumors were mostly found than symptomatic PETs (p<0.001). Equally lymph-node metastases (N1) were identified in 44.6% of patients with S-NF-PET (78 cases) versus a 20.6% of patients with incidental tumor (27 cases); p<0.001. One patient with I-NF-PET on stage I was found to have malignant disease; this patient initially was classified as benign and underwent enucleation with clear surgical margins (R0), but had liver disease recurrence after 28 months after surgical resection. In this case preoperative imaging evaluation demonstraded the main pancreatic duct (MPD) obstruction (> 5 mm) and a serotonin immunoreactivity at the immunohistochemical evaluation. From September 2007 to September 2011 a total of 19 patients with I-NF-PNET diagnosis were enrolled. All cases was classified as NET-G1 and median size was 15 mm (range 9 – 20). In all cases, no MPD obstruction was confirmed at preoperative imaging. All this patients refused surgical resection. Currently Follow-Up was available for all patients, with a median follow-up of 22 months (range 6 – 48). All Patients were alive, asymptomatic and with tumor stable in size and no evidence of progression disease. Conclusions: this study shows that patients with incidentally detected NF-PETs represent about 40% of resectable NF-PETs and frequency of incidental diagnosis was increasing in last years. Incidental detection seems to be an important favorable prognostic factor for histopathological features, patients overall survival and disease free survival. Anyway pancreatic surgery have a recognized high rate of perioperative morbidities and for < 20 mm and carefully selected pancreatic neuroendocrine “incidentalomas” a clinical-laboratory and radiographic surveillance might be possible.